Recovery release system



Aug. 26, 1969 A, YU 7 3,463,113

RECOVERY RELEASE SYSTEM Filed May 23, 1966 INVENTOR A.FRED FEYLING FIGA FIGZ

ATTORNEYS United States Patent 3,463,113 RECOVERY RELEASE SYSTEM Anders F. Feyling, Cambridge, Mass., assignor, by mesne assignments, to EC & G International, Inc., Bedford, Mass., a corporation of Delaware Filed May 23, 1966, Ser. No. 551,994 Int. Cl. B631: 9/00; E21b 43/00, 29/00 U.S. Cl. 114221 11 Claims ABSTRACT OF THE DISCLOSURE Underwater equipment or the like is released automatically from an anchor or securing mechanism at a predetermined time. A timer produces pulses during a predetermined interval at the end of which release is to be effected, and a squib pressure cartridge is energized to effect the release mechanically upon the counting of a predetermined number of pulses corresponding to the predetermined time interval.

The present invention relates to recovery release systems, being more specificaly directed to apparatus for enabling underwater equipment or the like automatically to be released or detached from an anchor or other securing mechanism at a predetermined time.

Among the problems attendant current release mechanisms of the above-described character is the reliability of the operating parts, such as motors and multiple switching mechanisms for controlling the timing of the release and the effecting of the same; it being evident that a failure results in the costly inability to recover expensive equipment. Other difi iculties, particularly of significance in underwater applications, include the possible drifting from the recovery zone of a prematurely or otherwise released apparatus, and, moreover, the dangers inherent in the present use of blade cutting or exploding bolt constructions for effecting the release.

An object of the present invention, accordingly, is to provide a new and improved recovery release apparatus that shall not be subject to the above difficulties, but that, rather, vastly increases the reliability, simplicity and safety of the apparatus and, optionally, provides for preventing the drifting of the released equipment. In summary, the former improvement is effected with the aid of novel electrical time delay apparatus cooperative with timer means and an electrically operable charge.

A further object is to provide a novel release apparatus of more general utility and application, as well.

Other and further objects will 'be explained hereinafter and will be more particularly pointed out in the appended claims.

The invention will now be described with reference to the accompanying drawings, FIG. 1 of which is a fragmentized side elevational view, partly in longitudinal section, of a preferred embodiment;

FIG. 2 is a schematic circuit diagram of the release mechanism of FIG. 1; and

FIGS. 3 and 4 are side elevations of modifications.

In the drawings, the invention is shown in connection with the illustrative example of an underwater application wherein a chain, cable, line, wire or other suspension 1, hereinafter generically referred to as a chain, connected with underwater equipment of any desired type (not shown), such as monitoring or sensing apparatus, is held submerged by an anchor or other mooring or securing mechanism 3. A release system 5, FIG. 1, is interposed between the chain 1 and a lower extension 1' thereof that is connected with the anchor 3. The release system 5 embodies within a water-tight container or housing 5' a timer 2, an electrical time delay circuit 4 adapted 3,463,113 Patented Aug. 26, 1969 upon the elapse of a desired predetermined time set by the timer to produce a release signal, a source of battery power 6, and a squib pressure cartridge or similar charge mechanism 8 responsive to the signal fed to it by conductor 8' to detach or release the apparatus 1-5 from the anchor chain 1'. The electrical circuit details are later described in connection with the preferred circuit of FIG. 2.

A mechanical linkage, providing mechanical advantage in the release from the anchor chain 1', is mounted below the housing 5 upon a block 26 and comprises a piston 12-14, intermediately provided with water-pressure sealing O-rings 16 and retracted in a bore 27, 27 (to the left in FIG. 1) in response to the pressure of the energized squib pressure cartridge 8, which is transmitted by chamber 28 to the right side of piston head 29. The piston head is driven against a replaceable anvil 10, preferably of plastic to prevent damage to the piston 12-14 when retracted. The piston 12-14 is normally held in place by a cotter pin or similar device 18. The water pressure acting on the end of piston 12-14 increases with depth, the piston being kept from retracting by pin 18.

With increased depth, less squib power is required for release and thus greater loads can be separated. The pin 18 becomes sheared upon operation of the squib cartridge 8, when piston 12-14 is driven to the left in FIG- URE 1, releasing a release link 20 and permitting a pivot bar 22 to turn about pivot 30 and drop the sling ring 24 connected to the mooring chain 1'. This mechanical linkage becomes thus opened at the desired time, releasing the system 1-5' from the anchor chain 1. The system 1-5 is then free to move upward in response to the buoyancy of float or buoy means (not shown) connected to chain 1, for recovery at the surface.

In the preferred circuit of FIG. 2, the timer 2 (such as a type Model A-190, manufactured by The Geodyne Corporation of Waltham, Mass.) is set to a predetermined time interval, the timer moving a multiple-contactor cam 7 to effect successive closures of a switch contactor device S at successive instants of time, such as every five-minute interval. Successive pulses of current are thus applied via resistor R to the base 9 of a first transistor Q from the junction I of capacitor C and resistor R that have stored energy from battery 6. The emitter 11 of Q is shown grounded at G and the collector output at 13 is applied via R" to the base 9' of a further transistor Q to apply the successive pulses to actuate successive counts in a time-delay relay RL connected in the collector circuit 13' of Q The emitter 11' of Q is connected through R' to the base 9 and thence to the terminal of the battery 6. A diode D is connected from the collector 13' to the ground terminal G to protect transistor Q When the successive pulses applied by the timer 2 to the time-delay relay RL correspond in number to the predetermined interval, at the end of which release is to occur say several months or a year or more, the relay RL becomes energized to switch contactor S to the right, sending a release signal through conductor 8' and the electrically operable squib cartridge 8. An on-olf switch S is also provided.

Through the elimination of motors and multiple switching apparatus, a simple and highly reliable time-release mechanism is thus provided. Redundancy may be employed, if desired, with a pair of units 5'-5", FIG. 3, the respective sling rings 24 and 24" of which may be linked by a common chain 25, in turn, passed through a link of the anchor chain 1. If only one ring 24 (or 24") is thus released, the apparatus will still release from the anchor chain.

There are some instances, moreover, where the released apparatus may be buoyed to the surface and drift away before it is recovered. To prevent this, a tether line L may be stored in folded fashion within a container 20 strapped adjacent the container with one end 22" secured to the apparatus 5" and the other end 27. connected to the anchor-chain sling ring 24, FIG. 4. The line ends 22 and 22 may pass through a slitted base rubber diaphragm 23 to retain the line before release is effected. When the sling ring is released and the apparatus 1-5 starts to move upward towards the surface, the tether line L will pay out and remain connected between the released apparatus and the anchor chain 1', thus preventing drifting. By using a readily fracturable line L, the recovery team may pull the line to break it and recover the apparatus.

Highly effective underwater release devices of the type shown and described have been successfully operated for many-day cycles of operation with a precision timer 2 turning a l2-lobed switching cam 7 at the rate of one revolution per hour and with a release time accuracy within sec/24 hours.

While preferred apparatus and circuits have been described, it is evident that other types of similar mechanism may be employed, including other types of time delay circuits and relay devices.

What is claimed is:

1. A system for releasing movable apparatus from a movement-preventing securing mechanism, that comprises timer means for controlling the production of a predetermined plurality of successive electrical pulses during a predetermined time interval at the end of which the release is to be effected, electrical time-delay means operable to count said plurality of successive electrical pulses during said interval of time, switching means controlled by said timer means and connected to apply successive electrical pulses to the time-delay means, means connected with the time-delay means and energizable to produce a release signal upon the counting by the time delay means of said predetermined plurality of pulses during the said predetermined time interval, and electrically operable release means responsive to said release signal for thereupon releasing the said apparatus from the securing mechanism, said apparatus being held under water by suspension means connected to the said securing mechanism and to mechanical linkage means connected with the said apparatus, and the said release means comprising means for opening said mechanical linkage means.

2. A system for releasing movable apparatus from a movement-preventing securing mechanism, that comprises timer means for controlling the production of a predetermined plurality of successive electrical pulses during a predetermined time interval at the end of which the release is to be effected, electrical time-delay means operable to count said plurality of successive electrical pulses during said interval of time, switching means controlled by said timer means and connected to apply successive electrical pulses to the time-delay means, means connected with the time-delay means and energizable to produce a release signal upon the counting by the timedelay means of said predetermined plurality of pulses during the said predetermined time interval, and electrically operable release means responsive to said release signal for thereupon releasing the said apparatus from the securing mechanism, said securing mechanism being coupled to said movable apparatus by a mechanical linkage, said release means comprising electrically operable squib means for opening said linkage.

3. A system as claimed in claim 1 and in which the release means further comprises an electrically operable squib pressure cartridge communicating with piston means for opening said linkage means.

4. A system as claimed in claim 3 and in which the linkage means comprises a member held by cotter-pin means shearable by the action of the pistion means, said member being releasably coupled to a release link in turn coupled to a pivot bar to which the suspension means is connected.

5. A system as claimed in claim 1 and in which camoperated switching means is provided controlled by the timer means for producing successive switch closures at successive predetermined controlled instants of time, said switch closures applying voltage pulses to said electrical time-delay means.

6. A system as claimed in claim 1 and in which two of said apparatus are provided and the said suspension means is connected to a further suspension means linked between the said mechanical linkage means of each apparatus.

7. A system as claimed in claim l and in which a tether line is stored adjacent said apparatus with one end connected to the apparatus and the other to the said suspension means in order that, upon the opening of the mechanical linkage means, releasing the suspension means from the said apparatus, the tether line will provide a fracturable drift-preventing connection between the released apparatus and the said suspension means.

8. Apparatus as claimed in claim 7 and in which the tether line is stored in folded fashion in container means secured to said apparatus.

9. Apparatus as claimed in claim 8 and in which the tether line is retained by slit diaphragm means.

10. A system for releasing underwater apparatus held by mechanical linkage means to secured suspension means, that comprises, timer means for presetting a predetermined time interval at the end of which the release is to be effected, means responsive at the end of said time interval for opening said mechanical linkage means to release said apparatus from said suspension means, and a tether line stored adjacent said apparatus with one end connected to the apparatus and the other to the said suspension means in order that, upon the said opening of the mechanical linkage means, the tether line will provide a fracturable drift-preventing connection between the released apparatus and the said suspension means.

11. A system as claimed in claim 2 and in which said linkage comprises a member shearable by the action of said squib means.

References Cited UNITED STATES PATENTS 3,124,723 3/1964 Stutz 317--l42 3,204,152. 8/1965 Ulrich 3 l7142 2,379,262 6/1945 Terry 317-142 2,567,928 9/1951 Farmer 317142 3,200,303 8/1965 Maxwell 317-142 3,326,172 6/1967 Kish 1l4221 MILTON BUCI-ILER, Primary Examiner THOMAS W. BUCKMAN, Assistant Examiner US. Cl. X.R. 

